Chlamydia pneumoniae:
Possible Association With
Asthma in Children
Chlamydia pneumoniae has been
recog-nized as a common cause of
communi-ty-acquired pneumonia (CAP) and
other acute respiratory infections (ARIs)
in various age groups [
1
]. Lately, the
prev-alence of Chlamydia-associated ARIs has
decreased to <1.5% [
2
], as a result of
changes in epidemiology of C.
pneumo-niae and increased speci
ficity of new
di-agnostic molecular methods. Moreover,
C. pneumoniae infection may remain
un-detected as clinicians may not screen the
infected population. Indeed, Chlamydia
pneumoniae has been recently identified
as an agent of asthma exacerbation
and has been associated with its severity
[
3
–
5
], thus reinforcing the importance
of targeting these patients. In Lausanne,
using a duplex real-time polymerase
chain reaction (PCR) that detects C.
pneumoniae and Mycoplasma
pneumo-niae DNA [
6
], we reported a 0.13%
prev-alence of C. pneumoniae–positive PCRs
(2/1583) and identi
fied 1 patient with C.
pneumoniae–associated asthma, who
re-covered with antibiotics [
7
]. Below, we
re-port a case series of C. pneumoniae
respiratory infections in children.
From 10 September to 5 December 2013,
C. pneumoniae was detected in upper
re-spiratory tract specimens from 8 children
(Table
1
). Of these, 5 were admitted for
either acute asthma exacerbation or
asth-matic bronchitis. All but 2 patients
present-ed with chronic cough without fever or
systemic symptoms. These two patients,
one with CAP who was coinfected with
M. pneumoniae (patient 7) and the other
one with severe asthma exacerbation who
was coinfected with rhinovirus (patient 8),
were admitted for severe respiratory distress
in the intensive care unit, intubated, and
mechanically ventilated. Both patients
with severe clinical presentation were
con-firmed asthmatics. All patients were
successfully treated with a macrolide.
In-terestingly, C. pneumoniae infection was
detected by chance in 7 patients as a result
of the dual format of our PCR, because a
M. pneumoniae PCR was requested.
In conclusion, this report supports the
role of C. pneumoniae in asthma
exacerba-tion. Whether C. pneumoniae-associated
asthma may be cured with antibiotics or
will also require steroids remains unknown
and may vary from patient to patient. This
case series underlines the importance of
screening asthmatic children for C.
pneu-moniae. Moreover, our
findings suggest
that C. pneumoniae prevalence is likely
un-derestimated and children with chronic
cough, even in absence of fever, should
be tested for C. pneumoniae.
Note
Potential conflicts of interest. All authors: No reported conflicts.
All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed.
Sandra A. Asner,1,2Katia Jaton,3 Sofiaanna Kyprianidou,1 Anna-Maria Libudzic Nowak,1and Gilbert Greub2,3
1
Unit of Pediatric Infectious Diseases and Vaccinology, Department of Paediatrics, University Hospital Center;
2
Service of Infectious Diseases, Department of Internal
Table 1.
Baseline Characteristics of Children Identi
fied With C. pneumoniae
Patient Age, y Sex Asthmatic Condition Cough
Duration Fever ICUa Sample
Copies/
mL Coinfection Treatment
Treatment Duration 1b 7 F Asthma Chronic Yes No Throat 1 743 796 No Clarithromycin 14 d
2 7 M Asthma Chronic Yes No Nasal 197 000 No Clarithromycin 10 d 3b 7 M None Chronic No No Throat 3100 No Clarithromycin 10 d
4 6 M None Chronic No No Nasal 60 No Azithromycin 5 d
5b 8 M Asthmatic
bronchitis
Chronic No No NP 78 000 No Clarithromycin 7 d 6b 12 F None Chronic No No NP 61 000 No Clarithromycin 7 d 7 7 F Asthma Acute Yes Yes NP 170 Mycoplasma
pneumoniae (570 copies/mL)
Clarithromycin 14 d
8 10 M Asthma Acute Yes Yes NP 208 Rhinovirus (13 071 000 copies/mL)
Erythromycin 14 d
Abbreviations: ICU, intensive care unit admission; NP, nasopharyngeal. a
Patient 7 was admitted to the ICU for community-acquired pneumonia; patient 8, for a severe asthma exacerbation. b
Patient originated from the same eastern region of Vaud canton (nearby Yverdon).
Medicine, University Hospital Center; and3Institute of Microbiology, Department of Laboratory, University of Lausanne and University Hospital Center, Switzerland
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Correspondence: Gilbert Greub, MD, PhD, Institute of Microbi-ology, Department of Laboratory, Rue du Bugnon 48, 1011 Lau-sanne (Vaud), Switzerland (gilbert.greub@chuv.ch). Clinical Infectious Diseases 2014;58(8):1198–9 © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals. permissions@oup.com.
DOI: 10.1093/cid/ciu034